Improvement in piano-locks



.1. WEBSTER.

Piano-Locks, &c.

Patented May 5,1874.

UNITED STATES PATENT OFFICE.,

JAMES WEBSTER, 0F DETROIT, MICHIGAN.

IMPROVEMENT IN PIANO-LOCKS, &c.

Specification forming part of Letters Patent No. 150,641, dated May 5, 1874; application filed February 2, 1874.

tain improvements in the construction of locks,

more especially' such as are employed on drawers, sewing-machine covers, and in other smi- 1lar places; and the invention consists in a novel construction and arrangement of theL principal operative parts in a lock, where the bolt is adapted for partial rotation, as well as retraction.

Figure lis a perspective view of my lock with the bolt forced out and partially rotated. Fig. 2 is a similar view of the rear side of the front plate. Fig. 3 is a like view of the inner side of the cap. Figt is a perspective of the caminto which the key is inserted to operate the lock. Fig. 5 isa detached perspective of the bolt. Fig. 6 is a detached view of the stop, which, when the key is withdrawn, prevents the lock from being operated by picklocks. Fig. 7 is aplan view of the lock with the cap removed. Fig. Sis a plan view of the key.

Like'letters indicate like parts in each figure.

In the annexed drawings, A represents the front plate of the lock, provided with a grooved bearing, a, upon which the bolt rests, and by which it is guided in being forced out and retracted; it is also provided with lugs b, into which are tapped suitable threads to engage with the screws by means of which cap is secured; it is also provided with a circular socket, c, into which the point of the key is inserted, Vand the wall of this socket enters the keyhole, and is swept by the points don the end of the key. D is au eccentric or cam, provided with key-hole e, and also with a rigid eccentric segment of a ring, h, so arranged as to leave a channel, m, which engages with a projecting head or end, i, of the bolt B, in such a manner that as the key turns the cam D, the bolt will be forced outward or retracted. One end of this ring h terminates in two or more ratchet-teeth, k, which engage with teeth a o n the end of the bolt, after the latter has been forced out, and partially rotate the same. The end of this bolt terminates in a T-head, Z, and when the bolt is partially rotated, as described, this head is designed to enter a suitable socket cutk at the inner end and athwart the hole or catch intowhich the bolt is forced. C is a stop, suitably pivoted in the slot r of the cam; its inner end is concave, as shown, to fit the convex win gs t of the key, and it is so placed and secured that as the key is inserted the outer end of the stop will be released depending upon the conformation of its inner end being the reverse of the -conformation ot' the win gs of the key, it follows that the lock cannot be opera-ted by any deviceexcept its own key, or a fac-simile thereof'.

What I claim as my invention, and desire to secure by Letters Patent, is y 1. In combination with the cam D, provided with teeth k, the bolt B, provided with teeth a and T-head Z, substantially as and for the purposes shown and described.

2. In combination, the cam D, provided with teeth L', the bolt B, provided with teeth a and T-head Z, and the stop C, the several parts constructed and arranged substantially as described and shown.

JAMES WEBSTER.

VVitnesr es z O. F. HUEsTIs, H. S. SPRAGUE. 

